Soil-fauna
Guides
Abdiunguis
Abdiunguis is a genus of minute rove beetles (family Staphylinidae, subfamily Pselaphinae) established in 1962. As a member of the tribe Trichonychini, it belongs to a diverse group of small beetles that inhabit leaf litter and soil microhabitats. The genus contains species with reduced elytra and compact body forms characteristic of pselaphine beetles.
Acari
Mites and Ticks, mites, ticks
Acari is a subclass of arachnids containing mites and ticks. The group exhibits extraordinary diversity with fossil records dating to the early Devonian period. Recent phylogenetic analyses have challenged the monophyly of Acari, suggesting that the two main lineages—Parasitiformes (ticks and allies) and Acariformes (dust mites, spider mites, chiggers, and allies)—may not share a single common ancestor exclusive of other arachnids. This would render Acari a paraphyletic or polyphyletic grouping rather than a natural taxon. The traditional unifying character, the gnathosoma (a modified mouthpart region), has been shown to be absent or differently constructed in many species across both lineages.
Achipterioidea
Achipterioidea is a superfamily of oribatid mites (Oribatida) within the order Sarcoptiformes. These mites are part of the diverse soil-dwelling microarthropod fauna. The superfamily was established by Thor in 1929 and is classified within the infraorder Brachypylina and the group Poronoticae.
Acylophorus pronus
Stooping Rove Beetle
Acylophorus pronus is a rove beetle in the family Staphylinidae, commonly known as the Stooping Rove Beetle. The species was described by Erichson in 1840 and is widely distributed across northern North America. As a member of the large genus Acylophorus, it inhabits moist terrestrial environments where it functions as a generalist predator or scavenger.
Adenosejus
Adenosejus is a genus of mites in the family Sejidae, order Mesostigmata. It was described in 2004 by Lekveishvili and Krantz. The genus belongs to the cohort Sejina, a group of large, heavily sclerotized mites often associated with soil and decomposing organic matter. As a recently described genus with limited subsequent study, its biology and ecology remain poorly documented.
Aleochara lucifuga
Aleochara lucifuga is a small rove beetle in the subfamily Aleocharinae, characterized by the abbreviated elytra typical of Staphylinidae. The species was described by Casey in 1893 and is documented from multiple eastern and central U.S. states. It belongs to a large genus of predatory rove beetles, though specific natural history details for this species remain poorly documented.
Aleocharinae
rove beetles
Aleocharinae is the largest subfamily of rove beetles (Staphylinidae), containing over 12,000 described species across more than 1,000 genera and 52 tribes. Members are predominantly small to minute beetles, typically 3–5 mm in length, with highly variable morphology reflecting their diverse ecological specializations. The subfamily exhibits extraordinary biological diversity, including free-living, myrmecophilous, termitophilous, parasitic, predatory, fungivorous, and herbivorous forms distributed across all terrestrial habitats worldwide.
Allacma
Allacma is a genus of springtails (Collembola) in the family Sminthuridae, first described by Börner in 1906. Members of this genus are globular springtails characterized by their compact, rounded body form typical of the order Symphypleona. The genus contains multiple species distributed across Europe and North America, with records extending to Arctic and Mediterranean regions. Allacma fusca, described by Linnaeus in 1758, is a well-known representative species.
Alliopsis
Alliopsis is a genus of root-maggot flies in the family Anthomyiidae, established by Schnabl and Dziedzicki in 1911. The genus contains at least 70 described species, though species-level taxonomy remains incompletely resolved. Members of this genus are small to medium-sized flies associated with soil and root habitats. The genus has been documented across northern Europe.
Allonychiurus
Allonychiurus is a genus of springtails (Collembola) in the family Onychiuridae, established by Yoshii in 1995. The genus includes species that inhabit soil ecosystems, with Allonychiurus kimi being particularly well-studied as an ISO-standardized soil bioindicator for ecotoxicology. Members are wingless and exhibit limited mobility, with some species showing negative phototaxis. The genus has been documented across Arctic, subarctic, and temperate regions including Europe and northeastern Eurasia.
Allonychiurus flavescens
Allonychiurus flavescens is a species of springtail in the family Onychiuridae. It is a small, soil-dwelling hexapod found in Pacific North American and Sino-Japanese regions. As an euedaphic collembolan, it lives deep within soil profiles and lacks a furcula (springing organ) typical of surface-dwelling springtails. The species was described by Kinoshita in 1916.
Allopauropus
Allopauropus is a genus of minute soil-dwelling myriapods in the class Pauropoda. These organisms belong to the order Tetramerocerata, characterized by four-segmented antennae. Pauropods are among the smallest myriapods, generally measuring under 2 mm in length, and are poorly studied due to their cryptic lifestyle in soil and leaf litter. The genus has been recorded from scattered localities across Europe, the Middle East, and South Asia.
Allopauropus carolinensis
Allopauropus carolinensis is a species of pauropod, a group of small, soil-dwelling myriapods in the class Pauropoda. Pauropods are among the least studied myriapod classes, characterized by their diminutive size and cryptic lifestyle in soil and leaf litter. The species was described by Starling in 1943 and is known from North America, with records from Ontario.
Americanura bara
Americanura bara is a species of springtail in the family Neanuridae, described by K. Christiansen and P. Bellinger in 1980. It belongs to the order Poduromorpha, a group of springtails characterized by their relatively short bodies and reduced furcula. The species is part of the genus Americanura, which contains several North American species. Distribution records indicate presence in northern and southern North America.
Anillina
A subtribe of minute ground beetles (Carabidae: Bembidiini) characterized by reduced eyes, elongated appendages, and adaptations for subterranean or cryptic habitats. Members exhibit convergent morphological traits associated with life in soil, leaf litter, or caves. The subtribe includes genera distributed across southern Gondwanan landmasses including New Zealand, Madagascar, and Australia, as well as the Northern Hemisphere.
Anillinus arenicollis
Anillinus arenicollis is a species of minute ground beetle in the family Carabidae. It belongs to a genus of small, often eyeless or reduced-eyed beetles adapted to subterranean or soil-dwelling habits. The species epithet 'arenicollis' suggests association with sandy habitats. Members of Anillinus are among the smallest carabid beetles and are poorly known due to their cryptic lifestyle.
Anillinus folkertsi
Anillinus folkertsi is a small ground beetle in the tribe Anillini (Carabidae), described from Alabama in 2004. Species in this genus are typically minute, eyeless or with reduced eyes, and adapted to life in soil and leaf litter habitats. The genus Anillinus is part of a diverse radiation of anilline ground beetles in eastern North America.
Anillinus jancae
Anillinus jancae is a small, eyeless ground beetle in the tribe Bembidiini. It was described by Thomas C. Barr in 1995 based on specimens from Kentucky. The species belongs to a genus of minute carabids adapted to subterranean or deep soil habitats. Like other Anillinus species, it exhibits troglomorphic traits including reduced pigmentation and vestigial eyes.
Anillinus micamicus
Anillinus micamicus is a species of minute ground beetle in the tribe Anillini, subfamily Bembidiinae. Species in this genus are characterized by their extremely small size, reduced eyes, and subterranean or soil-dwelling habits. Anillinus micamicus was described from specimens collected in the southeastern United States. Like other anillines, it is presumed to inhabit deep soil and leaf litter layers, where it occupies a cryptic lifestyle with limited surface activity.
Anillinus murrayae
Anillinus murrayae is a small ground beetle in the family Carabidae, described by Sokolov and Carlton in 2004. It belongs to the genus Anillinus, a group of minute, eyeless or nearly eyeless beetles adapted to subterranean and soil-dwelling lifestyles. The species is known from the United States. Like other members of its genus, it likely inhabits deep soil and leaf litter layers in forested environments.
Anotylus insignitus
Anotylus insignitus is a species of spiny-legged rove beetle in the family Staphylinidae. It has an exceptionally broad global distribution spanning six continents, including native ranges in the Neotropics and Caribbean, and introduced populations in North America, Europe, and Oceania. The species belongs to the tribe Oxytelini, a group characterized by fossorial (burrowing) habits and association with decaying organic matter.
Anurida granaria
granary short-legged springtail
Anurida granaria is a springtail species in the family Neanuridae, first described by Hercule Nicolet in 1847. It has been observed in a documented mycophagy association with the cup fungus Peziza arvernensis in southern Brazil, where a colony of over 500 individuals used a single fungal apothecium as both food source and living space. The species exhibits complete life cycle activities including molting, courtship behavior, and oviposition within fungal structures.
Anurophorinae
Anurophorinae is a subfamily of springtails (Collembola) within the family Isotomidae, established by Börner in 1901. Members of this subfamily are characterized by the absence of a furcula (springing organ), a trait reflected in the name 'Anurophorinae' (meaning 'tailless'). These small hexapods are part of the diverse soil and leaf litter fauna, contributing to decomposition processes. The subfamily is moderately well-represented in global collections with over 1,100 iNaturalist observations recorded.
Anurophorus near-septentrionalis
Anurophorus near-septentrionalis is a species of springtail in the family Isotomidae. It belongs to a genus of small, elongate collembolans found primarily in soil and leaf litter habitats. The specific epithet 'near-septentrionalis' suggests morphological similarity to A. septentrionalis, a northern-distributed species, though its precise taxonomic status may require verification.
Anystidae
whirligig mites
Anystidae is a family of predatory mites comprising over 100 species, commonly known as whirligig mites. They are active generalist predators found in soils and on vegetation worldwide. The family includes notable genera such as Anystis, Tarsotomus, and Chaussieria. Several species have been investigated for biological control potential against agricultural pests including thrips, aphids, and spider mites.
Anystina
Anystina is an infraorder of mites within the suborder Prostigmata (Trombidiformes). This group includes several families of relatively active, often predatory mites. Members are characterized by features of the gnathosoma and leg chaetotaxy that distinguish them from other prostigmatan lineages. The infraorder encompasses taxa such as Anystidae and related families, many of which occupy soil, leaf litter, and vegetation habitats.
Aptopus gracilis
Aptopus gracilis is a species of rove beetle in the family Staphylinidae, tribe Xantholinini. Members of this genus are characterized by their slender, elongated body form typical of many rove beetles. The species is distinguished from congeners by its gracile proportions and specific morphological details of the antennae and pronotum. Like other Xantholinini, it is likely associated with decaying organic matter and soil habitats, though specific ecological details for this species remain poorly documented in published literature.
Arrhopalites
springtails
Arrhopalites is a genus of globular springtails (Collembola: Symphypleona) in the family Arrhopalitidae. The genus comprises approximately 40 valid species, with roughly half considered troglobionts—obligate cave-dwelling organisms. Species occur across diverse habitats including cave systems, forest leaf litter, and soil environments, with distribution spanning the Neotropical Region, Asia, Europe, and other regions. The genus is taxonomically significant for phylogenetic studies of Symphypleona, though many aspects of its biology remain understudied.
Arrhopalites diversus
Arrhopalites diversus is a species of globular springtail in the family Arrhopalitidae, described by H.B. Mills in 1934. It belongs to the order Symphypleona, characterized by a rounded, globular body form. The species has been recorded from multiple regions across North America and the Caribbean. Like other members of its family, it inhabits soil and leaf litter environments.
Ascidae
Ascidae is a family of predatory mites in the order Mesostigmata. Members occupy diverse habitats including soil, litter, bark, and freshwater margins. Many species are phoretic, dispersing on larger arthropods such as beetles and flies. The family was historically broader, with Blattisociidae and Melicharidae now treated as separate families based on morphological distinctions.
Aspidoglossa
Aspidoglossa is a genus of ground beetles (family Carabidae) established by Putzeys in 1846. The genus comprises approximately 26 described species distributed primarily in the Neotropics, with a single species, Aspidoglossa subangulata, extending into the southern United States. These beetles belong to the subtribe Ardistomina within the tribe Clivinini, a group characterized by fossorial (burrowing) adaptations. The genus has been documented through 629 iNaturalist observations, indicating moderate levels of citizen science engagement.
Astenus cinctus
Astenus cinctus is a species of rove beetle in the family Staphylinidae, first described by Thomas Say in 1831. As a member of the subfamily Paederinae, it belongs to a diverse group of predatory beetles characterized by their elongated bodies and short elytra. The genus Astenus contains numerous species distributed across the Northern Hemisphere, with A. cinctus documented from parts of Canada and the United States.
Atheta particula
Atheta particula is a species of rove beetle in the family Staphylinidae, described by Casey in 1910. It belongs to the large and diverse subfamily Aleocharinae, one of the most species-rich lineages within the rove beetles. The species has been documented from limited observations in northeastern North America, with records from Canada and the northeastern United States. Like many aleocharine rove beetles, it is likely associated with decaying organic matter and soil habitats, though specific ecological details remain poorly documented.
Atheta pennsylvanica
Atheta pennsylvanica is a species of rove beetle described by Bernhauer in 1907. It belongs to the large genus Atheta within the subfamily Aleocharinae. The species is known from eastern North America, with records spanning Canada and the northeastern United States. Like other aleocharine rove beetles, it is small-bodied and associated with soil and leaf litter habitats.
Balaustiinae
Balaustiinae is a subfamily of mites in the family Erythraeidae, within the order Trombidiformes. Members are predatory erythraeoid mites characterized by specific morphological features in their leg chaetotaxy and body setation patterns. The subfamily was established by Grandjean in 1947 and contains multiple genera distributed across various terrestrial habitats.
Ballistura tuberculata
Ballistura tuberculata is a species of springtail in the family Isotomidae, described by J. Stach in 1947. It belongs to the order Entomobryomorpha, one of the major lineages of Collembola. The specific epithet 'tuberculata' suggests the presence of tubercle-like structures, though detailed morphological descriptions remain limited in available literature.
Batriasymmodes
Batriasymmodes is a genus of minute rove beetles in the family Staphylinidae, subfamily Pselaphinae, described by Orlando Park in 1951. Members of this genus belong to the tribe Batrisini, a diverse group of small beetles often associated with leaf litter and soil habitats. The genus is part of the hyperdiverse Pselaphinae, one of the most species-rich subfamilies of Staphylinidae, though individual species remain poorly documented in public databases. Observations of this genus are extremely sparse, with only five records in iNaturalist as of the available data.
Battigrassiella wheeleri
Battigrassiella wheeleri is a species of silverfish in the family Nicoletiidae, order Zygentoma. This small, wingless insect belongs to a group of primitive hexapods characterized by elongated bodies, three long tail-like appendages, and ametabolous development. Members of Nicoletiidae are typically found in concealed habitats such as soil, leaf litter, and caves. The genus Battigrassiella contains species adapted to subterranean or cryptic environments.
Bollmaniulus
Bollmaniulus is a genus of cylindrical millipedes in the family Parajulidae, order Julida. The genus was established by Verhoeff in 1926 and contains approximately 14 described species distributed primarily in western North America. Members of this genus are small to medium-sized juliform millipedes characterized by their relatively simple gonopod structure compared to related genera.
Bothriovulsus
Bothriovulsus is a genus of globular springtails (Symphypleona) in the family Dicyrtomidae, established by W.R. Richards in 1968. Members of this genus are small, soil-dwelling hexapods characterized by their rounded body form and reduced furcula. The genus is distributed across the Pacific North American, southern North American, and Sino-Japanese regions. Very few observations exist, with only four records documented on iNaturalist.
Bourletiella savona
Bourletiella savona is a species of globular springtail in the family Bourletiellidae, described by E.A. Maynard in 1951. As a member of the order Symphypleona, it possesses the characteristic rounded, globular body form distinct from the elongated shape of other springtail groups. The species is known from North America. Like other bourletiellid springtails, it inhabits soil and leaf litter environments where it contributes to decomposition processes.
Bourletiella viridescens
garden springtail
Bourletiella viridescens is a species of globular springtail (order Symphypleona) commonly known as the garden springtail. It was described by Stach in 1920 and has been recorded from Europe, the Azores, and Australia. A 2015 taxonomic revision established that Katianna coeruleocephala, described from Java in 1920 from a single collection, is a junior synonym of this species. The species inhabits moist organic substrates and is associated with decomposing plant material.
Brachycepsis
Brachycepsis is a genus of minute rove beetles in the subfamily Scydmaeninae, established by Brendel in 1889. Members of this genus belong to the tribe Stenichnini, a group characterized by small body size and specialized ecological associations. The genus is part of the diverse Staphylinidae family, one of the largest beetle families. Limited species-level information is available in public databases.
Brachygluta
ant-loving beetles
Brachygluta is a genus of ant-loving beetles (Staphylinidae: Pselaphinae) containing over 80 described species. These small rove beetles are specialist predators of mites. The Nearctic fauna has been revised, with 29 species recognized in North America.
Brachygluta ulkei
Brachygluta ulkei is a small rove beetle in the subfamily Pselaphinae, a diverse group of minute beetles often associated with leaf litter and soil habitats. The species was described by Brendel in 1866 and occurs in the eastern United States. Like other pselaphines, it is likely a predator or scavenger in microarthropod communities, though specific ecological details remain poorly documented.
Brachyglutini
Brachyglutini is a tribe of rove beetles in the subfamily Pselaphinae (family Staphylinidae). These beetles are minute, typically measuring 1–2 mm in length, and exhibit the characteristic compact body form and reduced elytra typical of pselaphine rove beetles. The tribe was established by Raffray in 1904 and contains numerous genera distributed across multiple continents. Members of this tribe are primarily found in forest litter and soil habitats where they function as micro-predators or scavengers.
Brachypauropodidae
Brachypauropodidae is a family of minute myriapods in the order Tetramerocerata, containing 33 species across seven genera. Members are characterized by specific tergite and sternite arrangements, with most adults possessing nine pairs of legs—though two genera (Aletopauropus and Zygopauropus) have only eight pairs. The family exhibits a nearly worldwide distribution, occurring on all continents except South America and Antarctica.
Brachypylina
Brachypylina is a diverse infraorder of oribatid mites (beetle mites) comprising the majority of oribatid species. These mites are characterized by heavily armored, beetle-like bodies with a distinct separation between the notogastral shield and other body regions. They occupy a wide range of terrestrial habitats and play significant roles in decomposition and nutrient cycling.
Brachystomella parvula
Brachystomella parvula is a species of springtail in the family Brachystomellidae, described by Schäffer in 1896. It belongs to the order Poduromorpha, a group of small hexapods characterized by reduced or absent furcula (springing organ) in some families. The species has been recorded from European localities, with additional distribution records from the Azores (Faial and São Miguel islands) and broader Atlantic regions.
Brachystomella villalobosi
Brachystomella villalobosi is a species of springtail described from Brazil in 1962. It belongs to the family Brachystomellidae, a group of small, soil-dwelling hexapods within the order Poduromorpha. The species is documented from northeastern and central Brazil, with records also from the Caribbean mainland. Very few observations exist, with only two records in iNaturalist.